The most recent version of the now popular DIY hydrogen car kits is called Half Water Half Gas, and it was developed by a man called Howard Hauk. The main motivation for people to use these guides and convert their car to run on water and gasoline as a hybrid is that they can save anywhere from 20-60% on fuel costs. Just the economic potential of using this technology is great, not to mention the really positive effect that it could have on the environment.So why is Half Water Half Gas any different from any of the other guides out there on the market. Well, the fact is that its based on the same system as the other guides. Even though pretty much all of the Do-It-Yourself guides are based on the same system, Half Water Half Gas manages to present the information in a new and fresh way and makes it easier to understand some of the trickier stages. The fact that the guide includes a video presentation of how to install the kit makes it a big winner over the others.